Britain's David Anthony, left, celebrates after scoring past Chuck Aoki, right, of the United States during a wheelchair rugby preliminary match at the 2012 Paralympics, Wednesday, Sept. 5, 2012, in London.

It doesn’t take long. Just a few minutes into the second quarter of the opening game between the U.S. and Great Britain, three players have slammed their wheelchairs hard into the opposition player carrying the ball, and none are disqualified for the intense tackle. Then, as British captain Steve Brown is flipped over in his wheelchair by his U.S. opponent, Derrick Helton, the commentator cries out to the full capacity crowd of 12,000 in the stadium: “Did you see that hit?” For those new to wheelchair rugby at this year’s Paralympic Games in London, it becomes obvious very quickly why it was christened murderball by fans.

A sport invented for quadriplegic athletes in Canada in the 1970s, murderball makes ice hockey look positively timid. Contact is allowed, even tactically encouraged. If a wheelchair is damaged, the team only has 60 seconds in which to repair it, or one crucial player is out of the game. While soccer players have a tendency to collapse into the fetal position at the hint of physical contact, wheelchair rugby players relish the opportunity for full-on collisions. Getting tipped over in your chair is to be expected, as are crushed fingers and bloody noses.

The sport is being drummed up as the main event of this Paralympics, with many British papers relishing the opportunity to play on the name: “Murderball teams prepare for slaughter” runs the headline from the Independent. The Guardian went with “It’s murder out there” following the first day of action, including an image of GB star David Anthony, sporting a striking blue mohawk roaring at teammate Aaron Phipps.

Still a relatively young sport, its popularity was fuelled by the 2005 Oscar nominated documentary Murderball, and tickets for the 2012 games sold out in just three days. Two of the U.S. players who were featured in the documentary still play for the team, the defending champions and favorites for this year’s crown along with the likes of Canada and Australia. They proved their worth with a 56-44 win over GB in the opener.

Despite its formal name, the game itself is an amalgamation of sports such as basketball, hockey and rugby. And while the brutality of it is often played up in the press, there are many cerebral, tactical aspects the game that make it such a rewarding spectator sport.

Many fans, in fact, liken it to chess, and it’s easy to see why: the players are in constant dialogue with each other as they attempt to score over the four, eight minute quarters of the game. Once a team has possession, they must score by carrying the ball over the end line within 40 seconds, or hand over possession to the opponent.

What adds to the drama, and allows teams to intercept the ball, is the requirement for players to pass or dribble the ball to their teammates within ten seconds. Failure to do so again means a change of possession. And while the game features some of the most disabled athletes at the Paralympics – players must have functional impairments to both their upper and lower limbs to be eligible – their speed and agility as they zoom across the regulation size basketball court can make it hard for spectators to keep up with the action.

The specially designed wheelchairs, which can cost nearly $8,000 each, are adapted differently for offensive and defensive players. They all come with anti-tip devices, attached to the back of the chair to make sure that players do not fall over easily. Despite this, broken bones are common to the game. Great Britain’s captain Steve Brown once broke six ribs and his sternum following a tackle. But many of these players have spinal cord injuries, and as a result, many claim that it makes them fearless.

Surprisingly breaking a bone is one of the lesser dangers players watch out for in the sport. Over-heating is much more of an immediate concern. One of the complications of spinal cord injuries is that the body’s ability to sweat below the level of the injury is diminished. Breaks between rounds are therefore crucial in allowing players to cool down.

Another defining feature of the sport is that it is not just for men of steel: it’s a mixed gender game. Still, despite this openness, there are only two women in the entire event across the eight teams. Kylie Grimes, of Team GB, is one of them. Speaking after the game against the U.S. to the Times of London, she said: “They treat me the same, that’s how it should be,” and then added, “it would be nice to see more women.”

Perhaps the spotlight on the game in London can attract more. Certainly the high-octane opening games from Wednesday showed the commitment from all players to put on a show. Medal hopefuls will need to have stamina though: the final takes place on Sunday and to reach it, teams will have to play – and dominate – over five consecutive days.